I'll try to give as as many details as possible for an easy diagnosis and solution. That's why the long post.

My grandparents got me a used T42 (XP SP2, 1.5 GHz processor) as a main computer, a role previously filled by a MacBook that is required by my school and has too many inherent problems to function property as my main machine. It is USED and lacks a warranty. It was fully serviced, apparently, by the tech staff at my grandpa's company. So you'd think it would be in fully working condition.

It has ThinkVantage (don't know if this is standard on all of them or what), so it uses that as the default wireless connections manager. The wireless adapter is Intel PRO/Wireless LAN 2100 3B Mini PCI. It won't get online. It DID get online, long enough for me to download FireFox (after having been interrupted several times by random disconnects). Now it won't work with FF or IE.

It's connected with Excellent signal strength to my house's router, a Linksys Wireless-B (yeah, I know) unit. It does not have security, and the computer is set to recognize this. I'm posting from the Mac now, which is connected to the very same network and is working fine. So it's not an ISP issue. In TV's Diagnostic Tools, you can test connection the internet. I've done this a bunch of times, and sometimes, it says connection okay (still won't connect) and sometimes is says unable to access the internet, despite the connection to the router. Error code is 018, it says: "internet is not responding. verify the config of your firewall program." tried this with the firewall disabled. nothin'.

Tried all the obvious things like resetting the modem and router, restarting the computer, and running all of the applicable wizards. Called IBM, but no warranty, no support for you. I see MAC address on here, but don't know what that means. Could that have anything to do with it?

"Using a Mac is not so much operating a computer as it is sort of tricking it- fooling it into doing what it is you really want it to do... you kind of have to sneak up on a Mac."
-Hunter Cressel

I am afraid that you have run into the same problem that I ran into when first connecting with a T series.

Can't say this any simpler. Replace your router. You will spend hours attampting to make this work (or may have already). No matter what you try it doesn't work. There is an incompatibility between the older Linksys router you describe and the T series wireless. I was never able to pinpoint the exact trouble but after spending hours and even days I could not get the wireless to work with that old Linksys wireless router.

Sorry to have to tell you this on your first post.

The good news is that after replacing this Linksys router the wireless worked perfectly instantly. So if you want to save some time, well I already said it.

Thanks. We've been meaning to do that anyways and this gave me a reason to actually go out and do it. It solved the problem to an extent, however one thing continues to be an issue: when I'm online, the wireless will occasionally "flicker" and reset the connection. The frequency of this has become frustrating, especially when in the middle of a IM conversation or trying to download a file. I think that the Mac sometimes "flickers" too, though it somehow manages to stay online while the connection resets and therefore it doesn't interrupt anything (though I'm not sure about this, it could be just the Mac's airport being weird). So this could be the ISP. Any ideas?

"Using a Mac is not so much operating a computer as it is sort of tricking it- fooling it into doing what it is you really want it to do... you kind of have to sneak up on a Mac."
-Hunter Cressel

I'm not really sure. The computer will sometimes just give me the little pop up from the toolbar that tells you that it's just connected to a network, and a page loading, download, or connection to pidgin (IM client) will suddenly be interrupted. If this is at all heard of on ThinkPads, then it might be the computer, but it's also possible for the router to be responsible. Any possible fixes on either end?

"Using a Mac is not so much operating a computer as it is sort of tricking it- fooling it into doing what it is you really want it to do... you kind of have to sneak up on a Mac."
-Hunter Cressel

This sounds like it could be your new router if both the thinkpad and macbook "flicker". Have you upgraded the router to its latest firmware?

I have a Linksys WRT54G and my Thinkpad T42 would disconnect a lot with the Linksys firmware. It was really frustrating. I thought it was the wireless card in my Thinkpad. But it ended up being my router. So I stumbled upon the DD-WRT firmware, and my connection has been rock solid ever since.

I wonder if it could have to do with your router's "lease time"? There is a setting in most every router that controls how long any connection is able to persist, at which point it will either renew your lease automatically (?your "flicker"?) or boot you off until you renew it (i.e., reconnect manually). This is just a guess, so take it for what it's worth . . .

My modem actually functions as both a modem and a router, so I configured it to work as a router as well (before, the linksys was doing the routing work, obviously) as the solution to this problem. i talked to my ISP and they said that they would send me a newer modem/router, since the one I'm using is outdated. Working on the mac, it doesn't have the same problem. The ISP's site says that intermittent connections can be caused by a virus. Is this possible?

"Using a Mac is not so much operating a computer as it is sort of tricking it- fooling it into doing what it is you really want it to do... you kind of have to sneak up on a Mac."
-Hunter Cressel